But aren’t diamonds merely carbon crystals formed at high pressure, so I imagine that it is very plausible, but not in the form of a polished version we see in ladies fingers.
Max, thanks for the book recommendations, I have read almost all Carl Sagan books, including Contact. Yet, we are so far the technology required, for human transport. That is just as well dream about it. :-)

The article said that it wouldn't look like a gigantic diamond ... but that just makes you wonder what it does look like ... I wonder of there are planets with diamonds the size of mountains on Earth, for example...